Combined wood turning and thread cutting device



c. c. TAYLOR 2,740,137 COMBINED WOOD TURNING AND THREAD CUTTING DEVICE A ril 3, 1956 Filed Dec. 31, 1951 CZVDE C. 71 794019, INVENTOR. BY 5 r? HTTOEA/EHS United States Patent COMBINED WOOD TURNING AND THREAD CUTTING DEVICE Clyde C. Taylor, Santa Ana, Calif. Application December 31, 1951, Serial No. 264,311

3 Claims. (Cl. 10-109) The present invention relates broadly to thread cutting devices and in particular to devices for cutting screw threads in the ends of wooden mop handles, broom handles and the like, and the arrangement described herein constitutes a simplification and improvement of the arrangement shown in my United States Letters Patent No. 2,549,141, patented April 17, 1951.

Wooden screw-threaded handles are used to a large extent as an attachment to a variety of cleaning devices such as brooms, mops, carpet sweepers and the like used in large quantities in restaurants, apartments, railroads, hotels, etc. Oftentimes these wooden handles break for one reason or another thereby rendering the associated cleaning device useless unless another handle is provided.

It is therefore an object of this invention to provide an improved device allowing the repair or complete fabrication of a screw-threaded handle in an easy, quick, simple and inexpensive manner.

Another object of the present invention is to provide a simple device of this character for cutting threads .in the ends of a wooden handle, either directly or after initial trimming of the handle to a desired diameter.

Another object of the present invention is to provide an improved thread-cutting device of this character which is simple, inexpensive to manufacture and which includes no relatively movable parts.

Although the thread-cutting device is described herein in connection with the repair of broom handles, it .is evident that its usefulness is not limited thereto but may be used to great advantage in the fabrication ofnew handles.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. This invention itself, both as to its organization and manner of operatiomtogether with further objects and advantages thereof, may be best understood by reference to the following description taken in connection with the accompanyingdrawings in which:

Figure l is a view in end elevation, looking at the back end of the device, incorporating features of the present invention, such view being taken as indicated by the lines 11 in Figure 3.

Figure 2 is a view taken substantially as .indicated by the lines 22 in Figure 1.

Figures 3 and 4 are views taken substantially on the lines 33 and 44 of Figure 2.

Figure 5 shows the shape of a rounded wooden handle in successive steps of operations performed thereon by the device shown in the previous figures.

The device shown herein is manufactured preferably from die-cast parts of a light, durable alloy and constitutes generally a unitary element having formed therein two cylindrical portions 11, 12 with cutting knives 13, 14 maintained in adjusted position by means of a screwthreaded clamping arrangement 15 which serves to maintain both of such cutting elements 13, 14 in adjusted relationship to the bores in the cylinders 11, 12, respectively.

This unitary element 10 is provided with a handle 17 2,740,137 l atented Apr. 3, 1956 which is shown herein as being allixed to the unitary element 10- by the screw-threaded bolt 18, the outer end of the handle 17 being provided with a nob 19 which is rotatably supported on the handle 17.

Briefly, as described in more detail hereinafter, the device is capable of performing the two functions indicated in Figure 5 on the end of a wooden circular pole or handle 20. The first of these two functions is to trim the end of the pole, as indicated at 20A, to provide the shoulder 20B thereon, the undercutting of the pole being performed by the cutting element 14, and thereafter, the second operation which constitutes cutting a screw thread 20C is performed by the other cutting element 13. For this purpose the end of the pole 20 is initially inserted into the cylindrical portion 12, and the device is turned, with the pole stationary, by applying a torque to the handle 17. After the handle is undercut, as shown at 20A, the woo-den undercut pole is inserted into the other cylindrical portion 11 and the device again is turned, but in the opposite direction, using the handle 17 and nob 19, so that the screw thread is cut bythe cutter 13.

To accomplish the above-mentioned results, the cylindrical portions 11, 12 have integrally formed therewith coaxially arranged cylindrical portions 11A, 12A, respectively, so as to provide a guide for the undercut pole end. The cylindrical portions 11, 12' are slightly larger than the diameter of the original pole end, while the diameter of the aligned cylindrical portions 11A, 12A are slightly larger than the diameter of the undercut pole end.

It is noted that the cylindrical portions 11, 12 are joined by an integrally formed web 21 which provides a seat for the lower end of the handle 17, such web 21 being tapped to receive the handle fastening bolt 18. It is understood, of course, that other means maybe provided to fasten the handle to the unitary structure 10 and the means shown herein for that purpose is merely exemplary of others.

It is further noted that the smaller aligned cylindrical portions 11A, 12A are also joined by an integrally formed web 23, such web 23 providing a base for maintaining the clamping arrangement 15 in locked position. The clamping arrangement 15 constitutes an apertured bar 24 having a pair of downwardly disposed legs 24A, 24B for engaging and pressing the right angle cutters 13, 14, respectively. A clamp fastening bolt 27- passes through the apertured portion of the bar 24 and is threaded in the web 23.

Both cutters 13, 14 have an identical L-shaped' cross section, but the cutter'1'4- is mounted for adjustable sliding movement on only one of 'its L-shaped legs, while the cutter 13 is mounted for adjustable sliding movement with both of its L-shaped cross sections engaging the base web In other words, the cutter 14 is clamped in a recess having a flat bottom 24E (Figure 3), while the cutter 13 is mounted in a recess having downwardly inclined walls 24F, 24G (Figure 4).

These cutters 13, 14 extend radially inwardly towards the cylindrical elements 11, 12 and generally tangential thereto, the cylindrical portion 12 being apertured at 30 for that purpose, while the base 23, for the same purpose, is apertured at 31 to accommodate the cutter 13.

it is observed that the cutters 13, 14 extend not only radially inwardly towards the cylindrical elements 11, 12 but are inclined somewhat, in the order of 5, in the direction of the forward end of the arrangement .into which the pole is inserted.

An important feature of the present arrangement resides in the means whereby the pitch of the wooden screw thread is determined. This means constitutes a protuberance 32 formed on the internal surface of the cylindrical portion 11A, such protuberance constituting, in effect, a fractional part of a screw thread and being, for that puta pose, inclined with respect to the longitudinal axis of the cylindrical element 11A an angular distance corresponding to the desired pitch of the screw thread. In other words, he angular position of the protuberance 32 with respect to the longitudinal axis of the cylindrical-element 11A determines the rate at which the pole may be fed into the cylindrical portion 11A upon turning the device with,

of course, the pole stationary. This protuberance 32 may I take different forms and shapes and may, for example, constitute an integral part of the cylindrical portion 11A, being formed simultaneously with the cylindrical portion 11A in a die-casting process; .in the alternative, such protuberance 32 may be produced simply by inserting a dowel pin through the cylindrical portion 11A with the walls of such cylindrical portion 11A maintaining the dowel pin in position.

In operation of the device, a Wooden pole having an end indicated at 20 in Figure is inserted into the cylindrical portion 12 and the device turned about the axis of the pole, the pole being either held in a vise or, if sumciently long, it may rest on the lloo-r with the operator holding the" free end of the pole against the floor with his foot and using one hand to hold the upper end of the pole andhis other hand to turn the device. The device is turned until the desired length of pole end is undercut, as indicated at 20A (Figure 5). The length of the undercut may be determined by the position of a stop member 35 located in the cylindrical portion 12A. Thereafter, the pole end is withdrawn from the cylindrical portion 12 and inserted into the cylindrical portion 11 for the subsequent thread forming operation. Such thread forming operation is accomplished by again turning the device about the axis of the wooden pole, but it being noted that in this case the device is turned in the opposite direction to form the screw threads 20C, as indicated in Figure 5.

In accomplishing the above purposes, the ends of the cutters 13, 14 are so adjusted that a portion of their free ends lies on a diameter passing through the aligned cylindrical portions 12, 12A on the one hand and 11, 11A on the other hand. Such diameters may be designated by the lines 3-3 and 4-4 in Figure 2.

While the particular embodiments of the present invention have been shown and described, it Will be obvious to those skilled in the art that change and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

Iclaim:

l. A rotary cutting tool, comprising: a pair of parallel extending tubular elements each having an elongated bore for receiving and guiding a workpiece and an aligned bore of smaller diameter for receiving and guiding an undercut portion of said workpiece; web means generally disposed 4 between said tubular elements and joining said tubular elements in a unitary structure; handle means releasably secured to said web means; one of said tubular elements having an aperture extending through its side wall and communicating with the elongated bore at approximately the position of the joining of this bore with the aligned bore of smaller diameter, and a cutter extending through said aperture into said elongated bore, said cutter having a substantially flat cutting edge to provide said workpiece with a cylindrically undercut portion; the other of said tubular elements having an aperture extending through its side wall on the same side of the tool as the first mentioned aperture and opening .into the bore of smaller diameter at a position approximately adjacent the joining of this bore with the elongated bore, a thread cutter extending through said aperture into the bore of smaller diameter, and an internal protuberance extending along the circumference of the bore of smaller diameter and being inclined with respect to the axis of the same to define the pitch of a screw thread, said thread cutter being in advance of said protuberance both axially and circumferentially with respect to the direction of rotation of the tool and the size of the cutter and the location of the protuberance being such as to provide a helical groove in said undercut portion of the workpiece; and common clamping means for said cutters whereby the same are simultaneously clamped to said web means, said clamping means including seats in said web means for the corresponding cutters. V

2. A rotary cuttingtool as defined in claim 1, wherein said clamping means further comprise a U-shapedbar having its downwardly extending legs engaging corresponding cutters, said bar being centrally apertured, and

a bolt passing through said apertured portion and engaging a screw-threaded portion in said Web means.

3. A rotary cutting tool as defined in claim 1, in which the cutters in said pair of tubular elements have identical L-shaped cross-sections, and in which the walls defining the aperture communicating with the elongated bore and the walls defining the corresponding seat in the web means provide means for mounting one of the cutters to present the fiat cutting edge of one of the legs of the cutter to the workpiece, and the walls defining the aperture communicating with the bore of smaller diameter and the walls of the corresponding seat in the web means provide means for mounting the other of the cutters to present the apex of the L-shaped cross-section of the cutter to the Work to thereby cut a Vshaped groove.

References Cited in the file of this patent UNITED STATES PATENTS 745,222 Mobeck Nov. 24, 1903 2,322,053 Palardy June 15, 1 943 2,549,141 Taylor Apr. 17, 1951 2,594,027 Iakeway Apr. 22, 1952 

